1. Field of the Invention
The present invention relates to a resin for sealing a compound semiconductor, a semiconductor device, and a process for manufacturing the semiconductor device. More specifically, it relates to a resin for sealing a compound semiconductor chip, a semiconductor device containing a compound semiconductor chip covered with a resin, and a process for manufacturing the semiconductor device.
2. Description of the Prior Art
Heretofore, as a resin for sealing a compound semiconductor, there has been used a resin (an addition reaction type silicone resin) obtained by adding an inorganic filler, a glass fiber or a curing catalyst to an addition reaction type siloxane compound (a compound having a --Si--O-- bond) as a matrix. When this addition reaction type silicone resin is subjected to the addition reaction under predetermined curing conditions, a silicone resin (an organosiloxane polymer) having a siloxane bond as a main chain can be produced, as shown in FIG. 1. In this example, the addition reaction of the siloxane compounds (--O--R.sub.2 Si--CH--CH.sub.2) and (H--R.sub.2 Si--O--) is carried out in the presence of a catalyst to produce the silicone resin (--O--R.sub.2 Si--CH.sub.2 CH.sub.2 --R.sub.2 Si--O--) (R is an organic group). The reasons why the addition reaction type silicone resin is used are that at the time of curing, solvent is not necessary and by-products are not formed to protect the compound semiconductor from contamination, and the curing can be completed in a short period of time by heating to contribute to the improvement of productivity. On the contrary, as for a resin containing a condensation reaction type siloxane compound as the matrix (a condensation reaction type silicone resin), an alcohol and water are generated at the time of the curing. Furthermore, the curing time of the condensation reaction type siloxane resin is relatively long, and the cured state of the resin is liable to change under the influence of the unevenness of temperature and moisture. For these reasons, the productivity is poor. In consequence, the condensation reaction type siloxane resin has not been used as the resin for sealing the compound semiconductor.
As described above, the addition reaction type silicone resin is excellent, but it still has some drawbacks. Even where a compound semiconductor chip, for example, a GaAlAs chip which functions as a luminous element is covered with the above-mentioned addition reaction type silicone resin and addition reaction is then carried out under predetermined curing conditions, the luminous output and withstand voltage (a reverse withstand voltage) decline and the characteristics of the chip also deteriorate, when the chip is continuously used.